Medical research

Women's menstrual cycles temporarily synchronize with moon cycles

The blog "Ladyplanet. Natürlich Frau sein" is quite certain: "Our cycle is linked to that of the moon. The most obvious connection is the length of the two cycles," it says. The newspaper Berliner Tagesspiegel comes to the ...


Does the moon affect our mood or actions?

Always surrounded by an aura of mystery, the moon and its possible influence over human behavior has been object of ancestral fascination and mythical speculation for centuries. While the full moon cannot turn people into ...


Bed-sharing linked to SIDS

(HealthDay)—Risk factors for sudden infant death syndrome (SIDS) appear to change with the age of the infant, researchers say.

Psychology & Psychiatry

Head out to the ski slopes, for happiness' sake

Are you contemplating a skiing holiday? The all-out pleasure and enjoyment you experience on a pair of skis or a snowboard is positively priceless to enhance your overall happiness. This is true even if you only get to go ...

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The Moon is Earth's only natural satellite and the fifth largest satellite in the Solar System. The average centre-to-centre distance from the Earth to the Moon is 384,403 km, about thirty times the diameter of the Earth. The common centre of mass of the system (the barycentre) is located about 1,700 km—a quarter the Earth's radius—beneath the surface of the Earth. The Moon makes a complete orbit around the Earth every 27.3 days (the orbital period), and the periodic variations in the geometry of the Earth–Moon–Sun system are responsible for the phases of the moon, which repeat every 29.5 days (the synodic period).

The Moon's diameter is 3,474 km, a little more than a quarter of that of the Earth. Thus, the Moon's surface area is less than a tenth that of the Earth (about a quarter the Earth's land area, approximately as large as Russia, Canada, and the United States combined), and its volume is about 2 percent that of Earth. The pull of gravity at its surface is about 17 percent of that at the Earth's surface.

The Moon is the only celestial body to which humans have traveled and upon which humans have performed a manned landing. While the Soviet Union's Luna program was the first to reach the Moon with unmanned spacecraft, the NASA Apollo program by the United States achieved the only manned missions to date, beginning with the first manned lunar mission by Apollo 8 in 1968, and six manned lunar landings between 1969 and 1972- the first being Apollo 11 in 1969. Human exploration of the Moon temporarily ceased with the conclusion of the Apollo program, although a few robotic landers and orbiters have been sent to the Moon since that time. The U.S. has committed to return to the moon by 2018.

This text uses material from Wikipedia, licensed under CC BY-SA